The technology relates to a vehicle power source that may be mounted on a vehicle.
As a vehicle power source that may be mounted on a vehicle, a power source have been proposed that allows a motor generator to perform regenerative power generation in vehicle deceleration (refer to Japanese Unexamined Patent Application Publication (JP-A) No. 2014-36557). In many cases, such a power source may charge electric power generated by the motor generator in not only a lead battery but also a lithium ion battery. This makes it possible to efficiently recover regenerative electric power in the vehicle deceleration, and to enhance energy efficiency of the vehicle.
Since the motor generator is coupled to an engine, not only may the motor generator perform the regenerative power generation in the vehicle deceleration, the motor generator may also be often driven as a starter motor at engine restart, or driven in vehicle acceleration in view of reduction in an engine load. Such positive utilization of the motor generator contributes to the enhancement in the energy efficiency of the vehicle. In recent years, power generation performance and output performance of the motor generator have shown a tendency of enhancement, in order to attain even higher energy efficiency.